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<h2><a name="SECTION00161410000000000000000"></a><a name="ctypes-ctypes-tutorial"></a>
<br>
14.14.1 ctypes tutorial
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<p>
Note: The code samples in this tutorial uses <code>doctest</code> to make sure
that they actually work.  Since some code samples behave differently
under Linux, Windows, or Mac OS X, they contain doctest directives in
comments.

<p>
Note: Quite some code samples references the ctypes <tt class="class">c_int</tt> type.
This type is an alias to the <tt class="class">c_long</tt> type on 32-bit systems.  So,
you should not be confused if <tt class="class">c_long</tt> is printed if you would
expect <tt class="class">c_int</tt> - they are actually the same type.

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<li><a href="ctypes-loading-dynamic-link-libraries.html">14.14.1.1 Loading dynamic link libraries</a>
<li><a href="ctypes-accessing-functions-from-loaded-dlls.html">14.14.1.2 Accessing functions from loaded dlls</a>
<li><a href="ctypes-calling-functions.html">14.14.1.3 Calling functions</a>
<li><a href="node453.html">14.14.1.4 Fundamental data types</a>
<li><a href="ctypes-calling-functions-continued.html">14.14.1.5 Calling functions, continued</a>
<li><a href="ctypes-calling-functions-with-own-custom-data-types.html">14.14.1.6 Calling functions with your own custom data types</a>
<li><a href="ctypes-specifying-required-argument-types.html">14.14.1.7 Specifying the required argument types (function prototypes)</a>
<li><a href="ctypes-return-types.html">14.14.1.8 Return types</a>
<li><a href="ctypes-passing-pointers.html">14.14.1.9 Passing pointers (or: passing parameters by reference)</a>
<li><a href="ctypes-structures-unions.html">14.14.1.10 Structures and unions</a>
<li><a href="ctypes-structureunion-alignment-byte-order.html">14.14.1.11 Structure/union alignment and byte order</a>
<li><a href="ctypes-bit-fields-in-structures-unions.html">14.14.1.12 Bit fields in structures and unions</a>
<li><a href="ctypes-arrays.html">14.14.1.13 Arrays</a>
<li><a href="ctypes-pointers.html">14.14.1.14 Pointers</a>
<li><a href="ctypes-type-conversions.html">14.14.1.15 Type conversions</a>
<li><a href="ctypes-incomplete-types.html">14.14.1.16 Incomplete Types</a>
<li><a href="ctypes-callback-functions.html">14.14.1.17 Callback functions</a>
<li><a href="ctypes-accessing-values-exported-from-dlls.html">14.14.1.18 Accessing values exported from dlls</a>
<li><a href="ctypes-surprises.html">14.14.1.19 Surprises</a>
<li><a href="ctypes-variable-sized-data-types.html">14.14.1.20 Variable-sized data types</a>
<li><a href="ctypes-bugs-todo-non-implemented-things.html">14.14.1.21 Bugs, ToDo and non-implemented things</a>
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